Solving the air-gap dilemma

By Derek B. Johnson

Jan 08, 2019

Although isolating sensitive IT systems from the internet with air gaps is secure and effective, it carries its own set of risks when information moves between air-gapped and connected systems. Now, the Defense Advanced Research Projects Agency is looking for innovations in hardware and software security that can better track and protect sensitive data as it moves from highly secure systems to insecure ones.

DARPA's Microsystems Technology Office at DARPA put out a call for research proposals for " the "Guaranteed Architecture for Physical Security," or GAPS, program, which is designed to address a security hole that lets hackers potentially gain access to data from an air-gapped system as it is being moved or transferred to other internet-facing systems.

"Today, modern computing systems are incapable of creating sufficient security protections such that they can be trusted with the most sensitive data while simultaneously being exposed to untrusted data streams," the broad agency announcement said.

While an air-gapped system can protect data at rest, a completely isolated system or computer often can be of limited value. Many must eventually interface with the internet indirectly or send and receive data from internet-connected systems where they are more vulnerable to a range of attacks. In 2015, a Chatham House report found a variety of methods through which air-gapped systems for nuclear power plants and other industrial control systems can be compromised, such as the use of physical flash drives that install malware and long-forgotten, unaccounted-for VPNs and other connections inherent in many older ICS networks.

As security researcher Bruce Schneier wrote in 2013, air-gaps are "conceptually simple, but they're hard to maintain in practice."

"The truth is that nobody wants a computer that never receives files from the Internet and never sends files out into the Internet," wrote Schneier. "What they want is a computer that's not directly connected to the Internet, albeit with some secure way of moving files on and off. But every time a file moves back or forth, there's the potential for attack."

That's essentially the dilemma DARPA is attempting to solve. Not only does the agency believe that current market capabilities are insufficient to verifiably and securely establish such file transfers between DOD systems with differing levels of security, but it believes the problem will only get worse as operational systems become more complex in the future.

As such, the office wants to approach the problem from a new perspective, ruling out current technologies and solutions like virtual machine managers, diodes or human fusion. Instead, the agency wants a better way to physically track the data it needs to protect.

"GAPS will create secure hardware and software co-design tools that physically isolate high risk transactions during both system design and system build, and track that such protections are physically enforced at runtime," the solicitation reads. "If a user wants to compute on sensitive data, the only true assurance is to physically track where the data is and guard all high-risk transactions."

The project will be split up into three technical areas: components and interfaces, co-design tools and integration and validation. DARPA wants compatibility across the board, so selected vendors or organizations will be required to sign an agreement to communicate and collaborate with each other throughout the project, and the notice encourages the use of combined submissions. Responses are due March 22.

Derek B. Johnson is a senior staff writer at FCW, covering governmentwide IT policy, cybersecurity and a range of other federal technology issues.

Prior to joining FCW, Johnson was a freelance technology journalist. His work has appeared in The Washington Post, GoodCall News, Foreign Policy Journal, Washington Technology, Elevation DC, Connection Newspapers and The Maryland Gazette.

Johnson has a Bachelor's degree in journalism from Hofstra University and a Master's degree in public policy from George Mason University. He can be contacted at [email protected], or follow him on Twitter @derekdoestech.